A child with Duchenne muscular dystrophy (DMD) and Mucopolysaccharidosis requires caries removal on tooth T. Which anesthetic technique is most appropriate?

Correct answer: C. PDL (periodontal ligament) infiltration

• A. The mental nerve block anesthetizes the anterior teeth and lower lip/chin but does NOT provide adequate anesthesia for primary molars or posterior mandibular teeth.
• B. Nitrous oxide is a sedative agent. In patients with DMD, volatile anesthetics and agents that affect respiratory function or muscle tone carry increased risk. Nitrous oxide should be used with caution or avoided in patients with DMD due to respiratory and cardiac comorbidities.
• C. CORRECT. PDL (periodontal ligament) infiltration is a targeted local injection directly into the PDL space of the tooth being treated. It provides effective pulpal anesthesia for the specific tooth without systemic sedation or the risks associated with volatile agents or deep sedation — making it the safest technique for a patient with DMD and mucopolysaccharidosis requiring caries removal.
• D. IAN block provides effective mandibular anesthesia, but requires the patient to cooperate for a standard injection depth. In DMD with mucopolysaccharidosis, systemic sedative agents should be minimized, and standard block techniques may not be ideal for a child needing just caries removal on a single primary tooth.